Project Summary Exposure to discrimination-related stressors (e.g., racial/ethnic discrimination, unfair treatment) continues to pose a public health challenge to minority populations as a social determinant of health. Although discrimination-related stressors have been consistently associated with poor mental health outcomes, there is a critical need to identify mechanisms and malleable risk/protective factors to integrate in the design of community and clinical interventions. The overall objective of this R01 application is to investigate mediators and moderators at multiple ecological (individual, family/peer and school/neighborhood levels) and time-scale (micro- and macro-time) levels in the link between discrimination-related stressors and mental health among 340 Mexican-origin youth. Guided by a socioecological, life course perspective, the proposed project has three specific aims: (1) determine within-person discrimination-related stressors that impact Mexican-American origin youth?s mental health outcomes as well as the mechanisms of action at both micro- and macro-time levels; (2) identify protective factors that could help youth to successfully cope with discrimination-related stressors and the conditions under which those protective factors work; and (3) elucidate the youth, parent, and neighborhood risk factors that moderate the link between discrimination-related stressors and mental health in youth. The project?s long-term goal is to improve the mental health of Mexican-origin youth by reducing the deleterious effects of racism, ?othering,? and negative neighborhood interactions. The central hypothesis is that this link will be mediated by cognitive and/or affective mechanisms (i.e. anger, hypervigilance, emotion regulation, low social position as threats to self-worth) and moderated by coping resources (parental adaptation and racial socialization) and family, peer, and neighborhood supports, thus representing multiple ecological levels. Community-based collaboration will help ensure recruitment of the targeted sample of Mexican-origin adolescents, mothers, and fathers; the inclusion of fathers will be a valuable contribution to the literature, given the dearth of studies on Latinx fathers/stepfathers. Through the innovative integration of both yearly longitudinal (macro-time) and daily diary (micro-time) research design features, important questions about how mediating and moderating processes unfold over time will be addressed. The proposed analyses also reflect the multi-layered sociocultural niches occupied by Latinx adolescents by employing individual-level methods as well as dyadic (adolescent-mother; adolescent-father) and triadic (adolescent-mother-father) analyses to test key study hypotheses. Considering the current growth of Latinx immigrants, it is imperative to test a socioecological model of risk and resilience for Mexican-origin adolescents that is responsive to both their immediate context and the larger global forces around migration. This research is highly translational in that it will facilitate the development of more effective, culturally sensitive prevention and intervention strategies for Latinx youth and their families.